Existing approaches in the fields of sewer refurbishing and concrete restoration and construction may involve the application of shotcrete, which may be pneumatically projected towards the surface in need of repair or construction. This shotcrete includes materials found in basic concrete, such as, sand, Portland cement, and liquid. At a particular job site, this shotcrete may take the form of either a dry-mix or a wet-mix application. The phrase “dry-mix” typically involves the pneumatic transfer of some or all of the materials in a dry state, through a hose, to a nozzle where an operator may control the application of liquid to the dry-mix at the nozzle prior to the projection of the substance. In contrast, the phrase “wet-mix” typically involves the transfer of a previously mixed concrete, including liquid, through a hose prior to projection.
Some companies have attempted to alter the material composition of the shotcrete in order to obtain certain benefits. Accordingly, some approaches may involve the use of geopolymers. However, these materials are often subject to corrosion as a result of the organic material inherent in these products. For example, Milliken® manufactures various products under their GeoSpray™ and GeoSpray™ AMS line of products. The AMS product may be applied as a pre and/or post-treatment to the GeoSpray™ product. GeoSpray is Portland cement-based and contains only a small portion of a geopolymer. This mixture is not acid stable. AMS contains organics to combat the effects of acids on Portland cement based concrete and of microbial induced corrosion that happens with Portland cement based materials.